Epidemiology of Pediatric Astrovirus Gastroenteritis in a Nicaraguan Birth Cohort.

Background: Astrovirus is a leading cause of acute gastroenteritis in children worldwide. However, few prospective studies have analyzed astrovirus in community-dwelling pediatric populations in low- and middle-income countries. Methods: We assessed the incidence, risk factors, clinical characteristics, genotypes, viral coinfections, and time distribution of astrovirus gastroenteritis in 443 healthy Nicaraguan children born in 2017 to 2018 who were followed for 36 months. Children were recruited from hospitals and birth records in an economically diverse neighborhood of León city. Astrovirus-positive episodes and genotypes were identified from stool with reverse transcription quantitative polymerase chain reaction and Sanger sequencing. Results: Of 1708 total specimens tested, 80 children (18%) experienced at least 1 astrovirus episode, and 9 experienced repeat episodes, mostly during the rainy season (May-October). Initial astrovirus episodes were not associated with a lowered risk against future episodes. In exploratory analyses, home toilets were associated with a lower risk of future astrovirus episodes (hazard ratio, 0.19; 95% CI, .04-.91). Human astrovirus 5 episodes, representing 15% of all typed episodes, were associated with longer diarrhea and more symptomatic rotavirus coinfections. Conclusions: Astrovirus was a common cause of gastroenteritis in this cohort, and future studies should clarify the role of astrovirus genotype in clinical infection severity.

Charting the impact of maternal antibodies and repeat exposures on sapovirus immunity in early childhood from a Nicaraguan birth cohort.

BACKGROUND: Sapovirus is an important cause of acute gastroenteritis in childhood. While vaccines against sapovirus may reduce gastroenteritis burden, a major challenge to their development is a lack of information about natural immunity. METHODS: We measured sapovirus-specific IgG in serum collected, between 2017 and 2020, of mothers soon after delivery and at 6 time points in Nicaraguan children until 3 years of age (n=112 dyads) using virus-like particles representing three sapovirus genotypes (GI.1, GI.2, GV.1). RESULTS: Sixteen (14.3%) of the 112 children experienced at least one sapovirus gastroenteritis episode, of which GI.1 was the most common genotype. Seroconversion to GI.1 and GI.2 was most common between 5 and 12 months of age, while seroconversion to GV.1 peaked at 18 to 24 months of age. All children who experienced sapovirus GI.1 gastroenteritis seroconverted and developed genotype-specific IgG. The impact of sapovirus exposure on population immunity was determined using antigenic cartography: newborns share their mothers' broadly binding IgG responses, which declined at 5 months of age and then increased as infants experienced natural sapovirus infections. CONCLUSION: By tracking humoral immunity to sapovirus over the first 3 years of life, this study provides important insights for the design and timing of future pediatric sapovirus vaccines.

Neurodevelopment in preschool children exposed and unexposed to Zika virus in utero in Nicaragua: a prospective cohort study.

BACKGROUND: Data on long-term neurodevelopmental outcomes of normocephalic children (born with normal head circumference) exposed to Zika virus in utero are scarce. We aimed to compare neurodevelopmental outcomes in normocephalic children up to age 48 months with and without Zika virus exposure in utero. METHODS: In this prospective cohort study, we included infants from two cohorts of normocephalic children born in León and Managua, Nicaragua during the 2016 Zika epidemic. In León, all women pregnant during the two enrolment periods were eligible. In Managua, mother-child pairs were included from three districts in the municipality of Managua: all women who became pregnant before June 15, 2016, and had a due date of Sept 15, 2016 or later were eligible. Infants were serologically classified as Zika virus-exposed or Zika virus-unexposed in utero and were followed up prospectively until age 48 months. At 36 months and 48 months of age, the Mullen Scales of Early Learning (MSEL) assessment was administered. Primary outcomes were MSEL early learning composite (ELC) scores at 30-48 months in León and 36-48 months in Managua. We used an inverse probability weighting generalised estimating equations model to assess the effect of Zika virus exposure on individual MSEL cognitive domain scores and ELC scores, adjusted for maternal education and age, poverty status, and infant sex. FINDINGS: The initial enrolment period for the León cohort was between Jan 31 and April 5, 2017 and the second was between Aug 30, 2017, and Feb 22, 2018. The enrolment period for the Managua cohort was between Oct 24, 2019, and May 5, 2020. 478 mothers (482 infants) from the León cohort and 615 mothers (609 infants) from the Managua cohort were enrolled, of whom 622 children (303 from the León cohort; 319 from the Managua cohort) were included in the final analysis; four children had microcephaly at birth and thus were excluded from analyses, two from each cohort. 33 (11%) of 303 children enrolled in León and 219 (69%) of 319 children enrolled in Managua were exposed to Zika virus in utero. In both cohorts, no significant differences were identified in adjusted mean ELC scores between Zika virus-exposed and unexposed infants at 36 months (between-group difference 1·2 points [95% CI -4·2 to 6·5] in the León cohort; 2·8 [-2·4 to 8·1] in the Managua cohort) or at 48 months (-0·9 [-10·8 to 8·8] in the León cohort; 0·1 [-5·1 to 5·2] in the Managua cohort). No differences in ELC scores between Zika virus-exposed and unexposed infants exceeded 6 points at any time between 30 months and 48 months in León or between 36 months and 48 months in Managua, which was considered clinically significant in other settings. INTERPRETATION: We found no significant differences in neurodevelopmental scores between normocephalic children with in-utero Zika virus exposure and Zika virus-unexposed children at age 36 months or 48 months. These findings are promising, supporting typical neurodevelopment in Zika virus-exposed normocephalic children, although additional follow-up and research is warranted. FUNDING: National Institute of Child Health and Development, National Institute of Allergy and Infectious Diseases, and Fogarty International Center. TRANSLATION: For the Spanish translation of the abstract see Supplementary Materials section.

Correction: Association between breastfeeding, host genetic factors, and calicivirus gastroenteritis in a Nicaraguan birth cohort.

[This corrects the article DOI: 10.1371/journal.pone.0267689.].

Transmission Patterns of Norovirus From Infected Children to Household Members in León, Nicaragua.

Norovirus is a common and highly transmissible gastrointestinal pathogen. Among 34 Nicaraguan households with a norovirus-infected child, 48% experienced norovirus transmission within 1 week, infecting 18% of household members; GII norovirus was more commonly transmitted than GI. Pediatric norovirus vaccines could prevent both index cases and transmission to close contacts.

Epidemiology of pediatric astrovirus gastroenteritis in a Nicaraguan birth cohort.

Background: Astrovirus is a leading cause of acute gastroenteritis in children worldwide. However, few prospective studies have analyzed astrovirus in community-dwelling pediatric populations in low-and-middle-income countries. Methods: We assessed the incidence, risk factors, clinical characteristics, genotypes, viral coinfections and seasonality of astrovirus gastroenteritis in 443 healthy Nicaraguan children born in 2017-2018, followed for 36 months. Children were recruited from maternity hospitals and birth records in an economically-diverse neighborhood of León, the second-largest city in Nicaragua. Astrovirus-positive episodes and genotypes were identified from diarrheal specimens with reverse transcription quantitative polymerase chain reaction and Sanger sequencing. Results: Of 1708 total specimens tested, eighty children (18%) experienced at least 1 astrovirus episode, and 9 experienced repeat episodes, mostly during the rainy season (May-October). The incidence of astrovirus episodes was 7.8/100 child-years (95% CI: 6.2, 9.8). Genotype-specific incidence of astrovirus also exhibited seasonality. Median age of astrovirus episode onset was 16 months (IQR 9, 23). Initial astrovirus episodes were not associated with protection against future episodes during the age span studied. Astrovirus cases were exclusively breastfed for a shorter period than uninfected children, and the human milk oligosaccharide lacto-N-fucopentaose-I was more concentrated in mothers of these children. Home toilets appeared to protect against future astrovirus episodes (HR=0.19, 95% CI 0.04-0.91). Human astrovirus-5 episodes, comprising 15% of all typed episodes, were associated with longer diarrhea and more symptomatic rotavirus co-infections. Conclusion: Astrovirus was a common cause of gastroenteritis in this cohort, and future studies should clarify the role of astrovirus genotype in clinical infection severity.

Nonsecretor Phenotype Is Associated With Less Risk of Rotavirus-Associated Acute Gastroenteritis in a Vaccinated Nicaraguan Birth Cohort.

BACKGROUND: Histo-blood group antigens (HBGAs) have been associated with rotavirus vaccine take; but the effect of these HBGAs on rotavirus incidence and risk remains poorly explored in vaccinated populations. METHODS: Rotavirus-associated acute gastroenteritis (AGE) was assessed in 444 Nicaraguan children followed from birth until 3 years of age. AGE episodes were tested for rotavirus by reverse-transcription quantitative polymerase chain reaction, and saliva or blood was used to determine HBGA phenotypes. Cox proportional hazards models were used to estimate the relative hazard of rotavirus AGE by HBGA phenotypes. RESULTS: Rotavirus was detected in 109 (7%) stool samples from 1689 AGE episodes over 36 months of observation between June 2017 and July 2021. Forty-six samples were successfully genotyped. Of these, 15 (35%) were rotavirus vaccine strain G1P[8], followed by G8P[8] or G8P[nt] (11 [24%]) and equine-like G3P[8] (11 [24%]). The overall incidence of rotavirus-associated AGE was 9.2 per 100 child-years, and was significantly higher in secretor than nonsecretor children (9.8 vs 3.5/100 child-years, P = .002). CONCLUSIONS: The nonsecretor phenotype was associated with decreased risk of clinical rotavirus vaccine failure in a vaccinated Nicaraguan birth cohort. These results show the importance of secretor status on rotavirus risk, even in vaccinated children.

Visual findings in children exposed to Zika in utero in Nicaragua.

Knowledge regarding the frequency of ocular abnormalities and abnormal visual function in children exposed to Zika virus (ZIKV) in utero but born without congenital Zika syndrome (CZS) is limited. We hypothesized that children exposed to ZIKV in utero born without CZS may have visual impairments in early childhood. We performed ophthalmic examination between 16 and 21 months of age and neurodevelopment assessment at 24 months of age with the Mullen Scales of Early Learning test (MSEL) on children enrolled in a cohort born to women pregnant during and shortly after the ZIKV epidemic in Nicaragua (2016-2017). ZIKV exposure status was defined based on maternal and infant serological testing. Visual impairment was defined as abnormal if the child had an abnormal ophthalmic exam and/or low visual reception score in the MSEL assessment. Of 124 children included in the analysis, 24 (19.4%) were classified as ZIKV-exposed and 100 (80.6%) unexposed according to maternal or cord blood serology. Ophthalmic examination showed that visual acuity did not differ significantly between groups, thus, 17.4% of ZIKV-exposed and 5.2% of unexposed had abnormal visual function (p = 0.07) and 12.5% of the ZIKV-exposed and 2% of the unexposed had abnormal contrast testing (p = 0.05). Low MSEL visual reception score was 3.2-fold higher in ZIKV-exposed than unexposed children, but not statistically significant (OR 3.2, CI: 0.8-14.0; p = 0.10). Visual impairment (a composite measure of visual function or low MESL visual reception score) was present in more ZIKV-exposed than in unexposed children (OR 3.7, CI: 1.2, 11.0; p = 0.02). However, the limited sample size warrants future investigations to fully assess the impact of in utero ZIKV exposure on ocular structures and visual function in early childhood, even in apparently healthy children.

Antibody Immunity to Zika Virus among Young Children in a Flavivirus-Endemic Area in Nicaragua.

Objective: To understand the dynamics of Zika virus (ZIKV)-specific antibody immunity in children born to mothers in a flavivirus-endemic region during and after the emergence of ZIKV in the Americas. Methods: We performed serologic testing for ZIKV cross-reactive and type-specific IgG in two longitudinal cohorts, which enrolled pregnant women and their children (PW1 and PW2) after the beginning of the ZIKV epidemic in Nicaragua. Quarterly samples from children over their first two years of life and maternal blood samples at birth and at the end of the two-year follow-up period were studied. Results: Most mothers in this dengue-endemic area were flavivirus-immune at enrollment. ZIKV-specific IgG (anti-ZIKV EDIII IgG) was detected in 82 of 102 (80.4%) mothers in cohort PW1 and 89 of 134 (66.4%) mothers in cohort PW2, consistent with extensive transmission observed in Nicaragua during 2016. ZIKV-reactive IgG decayed to undetectable levels by 6-9 months in infants, whereas these antibodies were maintained in mothers at the year two time point. Interestingly, a greater contribution to ZIKV immunity by IgG3 was observed in babies born soon after ZIKV transmission. Finally, 43 of 343 (13%) children exhibited persistent or increasing ZIKV-reactive IgG at ≥9 months, with 10 of 30 (33%) tested demonstrating serologic evidence of incident dengue infection. Conclusions: These data inform our understanding of protective and pathogenic immunity to potential flavivirus infections in early life in areas where multiple flaviviruses co-circulate, particularly considering the immune interactions between ZIKV and dengue and the future possibility of ZIKV vaccination in women of childbearing potential. This study also shows the benefits of cord blood sampling for serologic surveillance of infectious diseases in resource-limited settings.

Household Surveillance for Norovirus Gastroenteritis in a Nicaraguan Birth Cohort: A Nested Case-Control Analysis of Norovirus Risk Factors.

Norovirus causes a large proportion of pediatric acute gastroenteritis (AGE) worldwide, and no vaccines are currently available. To inform public health measures against norovirus gastroenteritis, we assessed risk factors in a case-control study nested in a birth cohort study in Nicaragua. Between June 2017 and January 2022, we followed children weekly for AGE episodes, and collected stool specimens from symptomatic children. Risk factors for AGE were collected during routine weekly visits. Norovirus was detected in stools using real-time reverse transcriptase polymerase chain reaction and positive specimens were genotyped using Sanger sequencing. We included 40 norovirus-positive AGE children matched 1:2 to controls and conducted bivariate and multivariable analyses of norovirus AGE risk factors. Among typeable norovirus infections, GII.4 were more severe than non-GII.4 (four/twenty-one vs. one/nine) and accounted for all emergency visits and hospitalizations. Adjusted conditional logistic regression found that female sex and higher length-for-age Z score were protective against norovirus AGE; a dirt floor in the home, sharing cups or bottles, and recent contact with someone with AGE symptoms were associated with norovirus AGE, though estimates were highly imprecise. Reducing contact with symptomatic persons and with saliva or other bodily fluids on cups or floors could reduce infant norovirus incidence.

Timing and genotype distribution of symptomatic and asymptomatic sapovirus infections and re-infections in a Nicaraguan birth cohort.

OBJECTIVES: To characterize the timing and genotype distribution of symptomatic and asymptomatic sapovirus infections and re-infections in a Nicaraguan birth cohort. METHODS: Infants (N = 444) were enrolled at 10-14 days of life and observed weekly until 2 years of age. Stool samples were collected for each acute gastroenteritis (AGE) episode, and routine stool samples were collected monthly. Stool samples were tested for sapovirus using RT-qPCR, and positive samples were genotyped. RESULTS: A total of 348 children completed 2 years of AGE weekly surveillance; 93 (26.7%) of them experienced sapovirus AGE. Most infections occurred after 5 months of age and mainly during the second year of life (62.4%, 58/93) and early in the rainy season. Sapovirus screening in all stools from a subset of 67 children who consistently provided samples showed sapovirus infections in 91 of 330 (27.6%) AGE episodes and in 39 of 1350 (2.9%) routine stools. In this subset, the median age at the first sapovirus AGE was 11.2 months (95% CI, 9.3-15.9 months); 38 of 67 (57%) children experienced re-infections, 19 symptomatic and 19 asymptomatic. On average, sapovirus re-infections were reported 7.2 months after symptomatic and 5.3 months after asymptomatic infections. Genogroup GI (64%, 69/108) was the most common detected. Sapovirus GI.1 was more frequently detected in AGE stool samples than in routine stool samples (47.2%, 43/91 vs. 25.6%, 10/39; p 0.005), and re-infection with the same genotype was uncommon. DISCUSSION: The first sapovirus infections occurred at approximately 11 months of age, whereas the median time to symptomatic re-infection was 7.2 months. Re-infections with the same sapovirus genotype were rare during 2 years of life suggesting genotype-specific protection after natural infection.

Association between breastfeeding, host genetic factors, and calicivirus gastroenteritis in a Nicaraguan birth cohort.

BACKGROUND: Norovirus and sapovirus are important causes of childhood acute gastroenteritis (AGE). Breastfeeding prevents AGE generally; however, it is unknown if breastfeeding prevents AGE caused specifically by norovirus and sapovirus. METHODS: We investigated the association between breastfeeding and norovirus or sapovirus AGE episodes in a birth cohort. Weekly data on breastfeeding and AGE episodes were captured during the first year of life. Stools were collected from children with AGE and tested by RT-qPCR for norovirus and sapovirus. Time-dependent Cox models estimated associations between weekly breastfeeding and time to first norovirus or sapovirus AGE. FINDINGS: From June 2017 to July 2018, 444 newborns were enrolled in the study. In the first year of life, 69 and 34 children experienced a norovirus and a sapovirus episode, respectively. Exclusive breastfeeding lasted a median of 2 weeks, and any breastfeeding lasted a median of 43 weeks. Breastfeeding in the last week did not prevent norovirus (HR: 1.09, 95% CI: 0.62, 1.92) or sapovirus (HR: 1.00, 95% CI: 0.82, 1.21) AGE in a given week, adjusting for household sanitation, consumption of high-risk foods, and mother's and child's histo-blood group phenotypes. Maternal secretor-positive phenotype was protective against norovirus AGE, whereas child's secretor-positive phenotype was a risk factor for norovirus AGE. INTERPRETATION: Exclusive breastfeeding in this population was short-lived, and no conclusions could be drawn about its potential to prevent norovirus or sapovirus AGE. Non-exclusive breastfeeding did not prevent norovirus or sapovirus AGE in the first year of life. However, maternal secretor-positive phenotype was associated with a reduced hazard of norovirus AGE.

Norovirus Infection in Young Nicaraguan Children Induces Durable and Genotype-Specific Antibody Immunity.

There are significant challenges to the development of a pediatric norovirus vaccine, mainly due to the antigenic diversity among strains infecting young children. Characterizing human norovirus serotypes and understanding norovirus immunity in naïve children would provide key information for designing rational vaccine platforms. In this study, 26 Nicaraguan children experiencing their first norovirus acute gastroenteritis (AGE) episode during the first 18 months of life were investigated. We used a surrogate neutralization assay that measured antibodies blocking the binding of 13 different norovirus virus-like particles (VLPs) to histo-blood group antigens (HBGAs) in pre- and post-infection sera. To assess for asymptomatic norovirus infections, stools from asymptomatic children were collected monthly, screened for norovirus by RT-qPCR and genotyped by sequencing. Seroconversion of an HBGA-blocking antibody matched the infecting genotype in 25 (96%) of the 26 children. A subset of 13 (50%) and 4 (15%) of the 26 children experienced monotypic GII and GI seroconversion, respectively, strongly suggesting a type-specific response in naïve children, and 9 (35%) showed multitypic seroconversion. The most frequent pairing in multitypic seroconversion (8/12) were GII.4 Sydney and GII.12 noroviruses, both co-circulating at the time. Blocking antibody titers to these two genotypes did not correlate with each other, suggesting multiple exposure rather than cross-reactivity between genotypes. In addition, GII titers remained consistent for at least 19 months post-infection, demonstrating durable immunity. In conclusion, the first natural norovirus gastroenteritis episodes in these young children were dominated by a limited number of genotypes and induced responses of antibodies blocking binding of norovirus VLPs in a genotype-specific manner, suggesting that an effective pediatric norovirus vaccine likely needs to be multivalent and include globally dominant genotypes. The duration of protection from natural infections provides optimism for pediatric norovirus vaccines administered early in life.

Gut Microbiome Changes Occurring with Norovirus Infection and Recovery in Infants Enrolled in a Longitudinal Birth Cohort in Leon, Nicaragua.

Noroviruses are associated with one fifth of diarrheal illnesses globally and are not yet preventable with vaccines. Little is known about the effects of norovirus infection on infant gut microbiome health, which has a demonstrated role in protecting hosts from pathogens and a possible role in oral vaccine performance. In this study, we characterized infant gut microbiome changes occurring with norovirus-associated acute gastroenteritis (AGE) and the extent of recovery. Metagenomic sequencing was performed on the stools of five infants participating in a longitudinal birth cohort study conducted in León, Nicaragua. Taxonomic and functional diversities of gut microbiomes were profiled at time points before, during, and after norovirus infection. Initially, the gut microbiomes resembled those of breastfeeding infants, rich in probiotic species. When disturbed by AGE, Gammaproteobacteria dominated, particularly Pseudomonas species. Alpha diversity increased but the genes involved in carbohydrate metabolism and glycan biosynthesis decreased. After the symptoms subsided, the gut microbiomes rebounded with their taxonomic and functional communities resembling those of the pre-infection microbiomes. In this study, during disruptive norovirus-associated AGE, the gut microbiome was temporarily altered, returning to a pre-infection composition a median of 58 days later. Our study provides new insights for developing probiotic treatments and furthering our understanding of the role that episodes of AGE have in shaping the infant gut microbiome, their long-term outcomes, and implications for oral vaccine effectiveness.

Neurological and neuropsychological sequelae of Zika virus infection in children in León, Nicaragua.

Objectives: To describe the presence and persistence of neurological and neuropsychological sequelae among children with acquired Zika virus infection and assess whether those sequelae were more common in children infected with Zika virus compared to uninfected children. Methods: We conducted a prospective cohort study of children with and without Zika virus infection in León, Nicaragua, using a standard clinical assessment tool and questionnaire to collect data on symptoms at three visits, about 6 months apart, and a battery of standardized instruments to evaluate neurocognitive function, behavior, depression, and anxiety at the last two visits. Results: Sixty-two children were enrolled, with no significant differences in demographics by infection group. Children infected with Zika virus had a range of neurological symptoms, some of which persisted for 6 to 12 months; however, no consistent pattern of symptoms was observed. At baseline a small percentage of children infected with Zika virus had an abnormal finger-to-nose test (13%), cold touch response (13%), and vibration response (15%) versus 0% in the uninfected group. Neurocognitive deficits and behavioral problems were common in both groups, with no significant differences between the groups. Children infected with Zika virus had lower cognitive efficiency scores at the 6-month visit. Anxiety and depression were infrequent in both groups. Conclusions: Larger studies are needed to definitively investigate the relationship between Zika virus infection and neurological symptoms and neurocognitive problems, with adjustment for factors affecting cognition and behavior, including mood and sleep disorders, home learning environment, history of neuroinvasive infections, and detailed family history of neuropsychological problems.

Neurological and neuropsychological sequelae of Zika virus infection in children in León, Nicaragua

[ABSTRACT]. Objectives. To describe the presence and persistence of neurological and neuropsychological sequelae among children with acquired Zika virus infection and assess whether those sequelae were more common in children infected with Zika virus compared to uninfected children. Methods. We conducted a prospective cohort study of children with and without Zika virus infection in León, Nicaragua, using a standard clinical assessment tool and questionnaire to collect data on symptoms at three visits, about 6 months apart, and a battery of standardized instruments to evaluate neurocognitive function, behavior, depression, and anxiety at the last two visits. Results. Sixty-two children were enrolled, with no significant differences in demographics by infection group. Children infected with Zika virus had a range of neurological symptoms, some of which persisted for 6 to 12 months; however, no consistent pattern of symptoms was observed. At baseline a small percentage of children infected with Zika virus had an abnormal finger-to-nose test (13%), cold touch response (13%), and vibration response (15%) versus 0% in the uninfected group. Neurocognitive deficits and behavioral problems were common in both groups, with no significant differences between the groups. Children infected with Zika virus had lower cognitive efficiency scores at the 6-month visit. Anxiety and depression were infrequent in both groups. Conclusions. Larger studies are needed to definitively investigate the relationship between Zika virus infec- tion and neurological symptoms and neurocognitive problems, with adjustment for factors affecting cognition and behavior, including mood and sleep disorders, home learning environment, history of neuroinvasive infec- tions, and detailed family history of neuropsychological problems.

[RESUMEN]. Objetivos. Describir la presencia y persistencia de secuelas neurológicas y neuropsicológicas en pacientes pediátricos que contrajeron la infección por el virus del Zika y evaluar si dichas secuelas fueron más comunes en los infectados con el virus del Zika en comparación con los no infectados. Métodos. Se realizó un estudio de cohorte prospectivo en pacientes pediátricos con y sin infección por el virus del Zika en León (Nicaragua), con una herramienta de evaluación clínica estándar y un cuestionario para recopilar datos sobre los síntomas en tres visitas, con aproximadamente seis meses de diferencia, y un con- junto de instrumentos estandarizados para evaluar la función neurocognitiva, el comportamiento, la depresión y la ansiedad en las últimas dos visitas. Resultados. Participaron 62 niños y niñas sin diferencias significativas en la demografía por grupo de infección. Los participantes infectados con el virus del Zika mostraron una variedad de síntomas neurológi- cos, algunos de los cuales persistieron entre 6 y 12 meses; no obstante, no se observó un patrón sistemático en los síntomas. Al inicio del estudio, un pequeño porcentaje de participantes infectados con el virus del Zika mostró resultados anormales a las pruebas dedo-nariz (13%), respuesta al tacto (frío) (13%) y respuesta a la vibración (15%), frente a un 0% en el grupo no infectado. Los déficits neurocognitivos y los problemas de comportamiento fueron comunes en ambos grupos, sin diferencias significativas entre los grupos. Los partic- ipantes infectados con el virus del Zika mostraron puntuaciones de eficiencia cognitiva más bajas en la visita a los 6 meses. La ansiedad y la depresión fueron poco frecuentes en ambos grupos. Conclusiones. Son necesarios estudios más amplios para investigar definitivamente la relación entre la infec- ción por el virus del Zika y los síntomas neurológicos y los problemas neurocognitivos, haciendo ajustes para los factores relacionados con la cognición y el comportamiento, incluidos los trastornos del estado de ánimo y el sueño, el entorno de aprendizaje en el hogar, los antecedentes de infecciones neuroinvasivas y los antecedentes familiares detallados de problemas neuropsicológicos.

[RESUMO]. Objetivos. Descrever a presença e a persistência de sequelas neurológicas e neuropsicológicas em crianças com infecção pelo vírus zika e avaliar se essas sequelas foram mais comuns em crianças infectadas pelo vírus zika em comparação com crianças não infectadas. Métodos. Realizamos um estudo de coorte prospectivo em crianças com e sem infecção pelo vírus zika em León, Nicarágua, usando uma ferramenta de avaliação clínica padrão e um questionário para coletar dados de sintomas em três consultas, com cerca de 6 meses de intervalo, além de um conjunto de ferramentas padronizadas para avaliar função neurocognitiva, comportamento, depressão e ansiedade nas duas últimas consultas. Resultados. Foram incluídas 62 crianças, sem diferenças significativas nas características demográficas por grupo de infecção. As crianças infectadas pelo vírus zika tinham uma gama de sintomas neurológicos, alguns dos quais persistiram por 6 a 12 meses. Entretanto, não se observou nenhum padrão consistente de sintomas. No início do estudo, uma pequena porcentagem de crianças infectadas com o vírus zika apresen- tou resultado anormal na prova índex-nariz (13%), resposta ao toque frio (13%) e sensibilidade vibratória (15%), em comparação a 0% no grupo não infectado. Déficits neurocognitivos e problemas comportamentais foram frequentes em ambos os grupos, mas sem diferenças significativas entre eles. As crianças infectadas com o vírus zika tiveram resultados mais baixos de eficiência cognitiva na consulta de 6 meses. Ansiedade e depressão não foram observadas com frequência em ambos os grupos. Conclusões. São necessários estudos mais amplos para investigar a relação exata entre a infecção pelo vírus zika e sintomas neurológicos e problemas neurocognitivos, com ajuste para fatores que afetam a cog- nição e o comportamento, incluindo distúrbios do humor e do sono, ambiente de aprendizagem em casa, história de infecções neuroinvasivas e história familiar detalhada de problemas neuropsicológicos.

First Episodes of Norovirus and Sapovirus Gastroenteritis Protect Against Subsequent Episodes in a Nicaraguan Birth Cohort.

BACKGROUND: Norovirus and sapovirus cause a large burden of acute gastroenteritis (AGE) in young children. We assessed protection conferred by norovirus and sapovirus AGE episodes against future episodes. METHODS: Between June 2017 and July 2018, we recruited 444 newborns in León, Nicaragua. Weekly household surveys identified AGE episodes over 36 months, and AGE stools were tested by reverse transcriptase-quantitative polymerase chain reaction (RT-qPCR) for norovirus genogroup (G)I/GII and sapovirus. We used recurrent-event Cox models and negative control methods to estimate protection conferred by first episodes, controlling for observed and unobserved risk factors, respectively. RESULTS: Sapovirus episodes conferred a 69% reduced hazard of subsequent episodes using the negative control method. Norovirus GI (hazard ratio [HR] = 0.67; 95% confidence interval [CI] = 0.31, 1.3) and GII (HR = 0.20; 95% CI = 0.04, 0.44) episodes also appeared highly protective. Protection against norovirus GII was enhanced following two episodes. CONCLUSIONS: Evidence of natural immunity in early childhood provides optimism for the future success of pediatric norovirus and sapovirus vaccines.

Rectovaginal Colonization with Serotypes of Group B Streptococci with Reduced Penicillin Susceptibility among Pregnant Women in León, Nicaragua.

Group B Streptococci (GBS) are important causes of neonatal sepsis and meningitis globally. To elucidate the potential benefits of maternal GBS vaccines, data is needed on the epidemiology of maternal GBS rectovaginal colonization, distribution of serotypes, and resistance to intrapartum antibiotic prophylaxis (IAP). We collected rectal and vaginal samples from 305 pregnant women in León, Nicaragua between 35 and 40 weeks gestation. Samples were cultured for GBS and confirmed using latex agglutination. GBS isolates underwent serotyping by quantitative polymerase chain reaction, and antimicrobial susceptibility testing by disk diffusion and microdilution following Clinical Laboratory Standard Institute guidelines. Sixty-three women (20.7%) were colonized with GBS in either the rectum or the vagina. Of 91 GBS isolates collected from positive cultures, most were serotypes II (28.6%), Ia (27.5%), and III (20.9%). Most GBS isolates (52.9%) were resistant to penicillin, the first-line prophylactic antibiotic. Penicillin resistance was highly correlated with resistance to vancomycin, ceftriaxone, and meropenem. The results of our study suggest that one-fifth of pregnant women in the urban area of León, Nicaragua are colonized with GBS and risk transmitting GBS to their offspring during labor. High resistance to commonly available antibiotics in the region suggests that prophylactic maternal GBS vaccination would be an effective alternative to IAP.

Secretor Status Strongly Influences the Incidence of Symptomatic Norovirus Infection in a Genotype-Dependent Manner in a Nicaraguan Birth Cohort.

BACKGROUND: The role of histo-blood group on the burden and severity of norovirus gastroenteritis in young infants has not been well documented. METHODS: Norovirus gastroenteritis was assessed in 443 Nicaraguan children followed from birth until 3 years of age. Stool samples were tested for norovirus by reverse-transcription quantitative polymerase chain reaction (RT-qPCR), and histo-blood group antigens (HBGAs) were determined by phenotyping of saliva and blood. Hazard ratios and predictors of norovirus acute gastroenteritis (AGE) outcome stratified by HBGA were estimated using Cox proportional hazards models. RESULTS: Of 1353 AGE episodes experienced by children, 229 (17%) tested positive for norovirus with an overall incidence of 21.9/100 child-years. Secretor children were infected as early as 2 months of age and had a higher incidence of norovirus GII compared to nonsecretor children (15.4 vs 4.1/100 child-years, P = .006). Furthermore, all GII.4 AGE episodes occurred in secretor children. Children infected with GI (adjusted odds ratio [aOR], 0.09 [95% confidence interval {CI}, .02-.33]) or non-GII.4 viruses (aOR, 0.2 [95% CI, .07-.6]) were less likely to have severe AGE compared to GII.4-infected children. CONCLUSIONS: Secretor status in children strongly influences the incidence of symptomatic norovirus infection in a genogroup or genotype-dependent manner and provides evidence that clinical severity in children depends on norovirus genotypes.

Neurological and neuropsychological sequelae of Zika virus infection in children in León, Nicaragua / Secuelas neurológicas y neuropsicológicas de la infección por el virus del Zika en niños y niñas en León, Nicaragua / Sequelas neurológicas e neuropsicológicas da infecção pelo vírus zika em crianças em León, Nicarágua

ABSTRACT Objectives. To describe the presence and persistence of neurological and neuropsychological sequelae among children with acquired Zika virus infection and assess whether those sequelae were more common in children infected with Zika virus compared to uninfected children. Methods. We conducted a prospective cohort study of children with and without Zika virus infection in León, Nicaragua, using a standard clinical assessment tool and questionnaire to collect data on symptoms at three visits, about 6 months apart, and a battery of standardized instruments to evaluate neurocognitive function, behavior, depression, and anxiety at the last two visits. Results. Sixty-two children were enrolled, with no significant differences in demographics by infection group. Children infected with Zika virus had a range of neurological symptoms, some of which persisted for 6 to 12 months; however, no consistent pattern of symptoms was observed. At baseline a small percentage of children infected with Zika virus had an abnormal finger-to-nose test (13%), cold touch response (13%), and vibration response (15%) versus 0% in the uninfected group. Neurocognitive deficits and behavioral problems were common in both groups, with no significant differences between the groups. Children infected with Zika virus had lower cognitive efficiency scores at the 6-month visit. Anxiety and depression were infrequent in both groups. Conclusions. Larger studies are needed to definitively investigate the relationship between Zika virus infection and neurological symptoms and neurocognitive problems, with adjustment for factors affecting cognition and behavior, including mood and sleep disorders, home learning environment, history of neuroinvasive infections, and detailed family history of neuropsychological problems.

RESUMEN Objetivos. Describir la presencia y persistencia de secuelas neurológicas y neuropsicológicas en pacientes pediátricos que contrajeron la infección por el virus del Zika y evaluar si dichas secuelas fueron más comunes en los infectados con el virus del Zika en comparación con los no infectados. Métodos. Se realizó un estudio de cohorte prospectivo en pacientes pediátricos con y sin infección por el virus del Zika en León (Nicaragua), con una herramienta de evaluación clínica estándar y un cuestionario para recopilar datos sobre los síntomas en tres visitas, con aproximadamente seis meses de diferencia, y un conjunto de instrumentos estandarizados para evaluar la función neurocognitiva, el comportamiento, la depresión y la ansiedad en las últimas dos visitas. Resultados. Participaron 62 niños y niñas sin diferencias significativas en la demografía por grupo de infección. Los participantes infectados con el virus del Zika mostraron una variedad de síntomas neurológicos, algunos de los cuales persistieron entre 6 y 12 meses; no obstante, no se observó un patrón sistemático en los síntomas. Al inicio del estudio, un pequeño porcentaje de participantes infectados con el virus del Zika mostró resultados anormales a las pruebas dedo-nariz (13%), respuesta al tacto (frío) (13%) y respuesta a la vibración (15%), frente a un 0% en el grupo no infectado. Los déficits neurocognitivos y los problemas de comportamiento fueron comunes en ambos grupos, sin diferencias significativas entre los grupos. Los participantes infectados con el virus del Zika mostraron puntuaciones de eficiencia cognitiva más bajas en la visita a los 6 meses. La ansiedad y la depresión fueron poco frecuentes en ambos grupos. Conclusiones. Son necesarios estudios más amplios para investigar definitivamente la relación entre la infección por el virus del Zika y los síntomas neurológicos y los problemas neurocognitivos, haciendo ajustes para los factores relacionados con la cognición y el comportamiento, incluidos los trastornos del estado de ánimo y el sueño, el entorno de aprendizaje en el hogar, los antecedentes de infecciones neuroinvasivas y los antecedentes familiares detallados de problemas neuropsicológicos.

RESUMO Objetivos. Descrever a presença e a persistência de sequelas neurológicas e neuropsicológicas em crianças com infecção pelo vírus zika e avaliar se essas sequelas foram mais comuns em crianças infectadas pelo vírus zika em comparação com crianças não infectadas. Métodos. Realizamos um estudo de coorte prospectivo em crianças com e sem infecção pelo vírus zika em León, Nicarágua, usando uma ferramenta de avaliação clínica padrão e um questionário para coletar dados de sintomas em três consultas, com cerca de 6 meses de intervalo, além de um conjunto de ferramentas padronizadas para avaliar função neurocognitiva, comportamento, depressão e ansiedade nas duas últimas consultas. Resultados. Foram incluídas 62 crianças, sem diferenças significativas nas características demográficas por grupo de infecção. As crianças infectadas pelo vírus zika tinham uma gama de sintomas neurológicos, alguns dos quais persistiram por 6 a 12 meses. Entretanto, não se observou nenhum padrão consistente de sintomas. No início do estudo, uma pequena porcentagem de crianças infectadas com o vírus zika apresentou resultado anormal na prova índex-nariz (13%), resposta ao toque frio (13%) e sensibilidade vibratória (15%), em comparação a 0% no grupo não infectado. Déficits neurocognitivos e problemas comportamentais foram frequentes em ambos os grupos, mas sem diferenças significativas entre eles. As crianças infectadas com o vírus zika tiveram resultados mais baixos de eficiência cognitiva na consulta de 6 meses. Ansiedade e depressão não foram observadas com frequência em ambos os grupos. Conclusões. São necessários estudos mais amplos para investigar a relação exata entre a infecção pelo vírus zika e sintomas neurológicos e problemas neurocognitivos, com ajuste para fatores que afetam a cognição e o comportamento, incluindo distúrbios do humor e do sono, ambiente de aprendizagem em casa, história de infecções neuroinvasivas e história familiar detalhada de problemas neuropsicológicos.